Funny because I already have a IW 10% lower on there that I bought and I’m not going to use now because I didn’t want to bother pulling it. Now the 15% lower I have on the car isn’t going to work because it’s probably going to make 21psi which is too much for pump gas and if I go bigger on the blower pulley it may not clear the hood per Whipple. So now it looks like I need to buy a 5% lower lol.
I think anything 5% will have to be done up top, I have never seen anything less than 10% for the lower?.....but maybe there is and I have missed it....
.......and yes, at the 15% lower there are some things that need to be considered....more than at 10%...
R